一种基于单像素指纹边界的信息隐藏技术

利用信息隐藏技术提高身份认证系统的安全性是一种有效方法,通过将用户身份信息中的指纹、人脸以及口令融合进行多模态认证提高身份认证安全性。而将口令信息嵌入到指纹图像中实现口令信息的隐藏及存储,既能够满足安全认证的需要,又能够保证口令存储的安全性能。本文首先介绍了基于指纹图像为载体的口令信息隐藏技术,然后将细化后指纹图像按单元块进行像素划分,再将口令信息按照Hash函数嵌入到单元中心像素点上,相当于构成一个二元信息稀疏矩阵。该方法不仅保证了指纹图像的质量,还确保了指纹图像骨架脊线的质量,从而确保了指纹识别的精度。最后,通过实验结果表明,本文提出的基于单像素指纹边界的信息隐藏技术能够较好地将信息嵌入到指纹图像中,具有较低修改率的同时提高了PSNR峰值信噪比量,而且与其它方法相比,本文提出的方法对指纹识别正确率影响较小。     

一种基于单像素指纹边界的信息隐藏技术

利用信息隐藏技术提高身份认证系统的安全性是一种有效方法，通过将用户身份信息中的指纹、人脸以及口令融合进行多模态认证提高身份认证安全性。而将口令信息嵌入到指纹图像中实现口令信息的隐藏及存储，既能够满足安全认证的需要，又能够保证口令存储的安全性能。本文首先介绍了基于指纹图像为载体的口令信息隐藏技术，然后将细化后指纹图像按单元块进行像素划分后，将口令信息按照Hash函数嵌入到单元中心像素点上，相当于构成一个二元信息稀疏矩阵，该方法不仅保证了指纹图像的质量，还确保了指纹图像骨架脊线的质量，从而确保了指纹识别的精度。最后，通过实验结果表明，本文提出的基于单像素指纹边界的信息隐藏技术能够较好地将信息嵌入到指纹图像中，具有较低修改率的同时提高了PSNR峰值信噪比量，而且与其它方法相比，本文提出的方法对指纹识别正确率影响较小。
     

针对指纹模板的可逆信息隐藏编码方法

通过融合指纹、人脸、口令等用户身份信息来进行多模态认证可以提高身份认证系统的安全性.而利用信息隐藏技术,可以将几种身份信息嵌入到某一种生物模板中实现安全存储.本文介绍了一种以指纹模板为隐藏载体的多模态认证技术,该技术的关键问题是要保证嵌入信息后的指纹图片的质量,以确保匹配的精度.为此,提出了一种将二元信息稀疏化的数据嵌入编码方法,利用这种编码可以有效降低数据嵌入过程中对指纹图片的修改,从而改善载密图片的质量,以达到提高匹配精度的目的.该方法嵌入脆弱水印,用于指纹模板的完整性认证.     

基于二维条码的指纹特征信息隐藏方法研究

提出了一种将指纹特征信息隐藏在二维条码中的指纹信息保护方法．利用指纹图像的方向信息和频率信息确定二值化的阈值，采用PDF417条码的编码、译码技术实现指纹图像的预处理和特征提取，并将提取结果嵌入到二维条码中，当对指纹进行认证时，从二维条码中读取数据并解码，得到存储的指纹特征信息，从而达到认证、鉴别的目的．实验结果表明，所提方法可提高指纹特征信息的安全性，且识别、认证效率比较高，实现了指纹特征信息的远距离安全传输和高速录入，以及在线、离线的认证．     

指纹图像预处理算法研究

在指纹识别系统中，指纹图像预处理是指纹特征提取与识别的前提．对指纹图像预处理技术进行了研究。提出了一种指纹图像预处理算法．实验结果显示，该算法能够去除指纹噪声，得到较高质量的指纹图像．     

eBiopass数字生物信息护照——指纹与IC卡的完美结合

随着财富的日渐积聚,个人财产的保护意识也逐渐强烈。越来越多的场合需要安全可靠的身份认证。于是,一种运用先进的生物识别领域知识与技术,基于个人的生物信息,代替传统的照片、密码、口令、钥匙,实现个体身份认证的解决方案产生了。 该方案是杭州中正生物认证技术有限公司利用其自主知识产权的指纹识别算法,结合PKI加密技术,以其高效的JusTouch(TM)指纹识别模块为基础建立的一个身份认证解决方案,是业内第一个脱机的指纹身份卡解决方案。其核心问题是比较已经利用PKI技术进行加密的存储在IC卡上的指纹模版与持有者的指纹是否…     

一种新的二值图像信息隐藏方法

随着数字媒体的普及,人们已经提出了许多在灰度图像和彩色图像中隐藏信息的方法,但是由于随意修改二值图像的像素值容易引起图像质量的明显下降,所以大多数在灰度图像和彩色图像中隐藏信息的方法不能直接应用到二值图像中.本文提出了一种在二值图像中进行信息隐藏的方法.该方法将二值图像分割成大小为2×2的图像块,利用图像块的奇偶性将一条二进制信息嵌入到黑白像素邻近的块中,嵌入1位信息平均修改0.5个像素,具有计算量小、嵌入信息量大、图像质量下降少、安全性高的优点.     

基于指纹识别技术的网络身份认证系统

在Internet/Intranet的应用中，其安全性面临着严重的挑战。用户在进入系统时，传统方法是通过口令验证其身份。这在某种程序上虽确保了计算机系统的安全，但同时存在着记忆烦琐、易丢失、易遗忘的弊端。针对这一问题，研究了以指纹代替传统的口令输入，设计了一套基于指纹识别技术的网络身份认证系统。     

基于NTRU的密文域可逆信息隐藏算法

NTRU (number theory research unit)具有抗量子计算攻击、加解密速度快、安全性高的特点,非常适合用于无线保密数据网、认证系统等业务。结合可逆信息隐藏技术,提出了一种基于NTRU的密文域可逆信息隐藏算法。首先利用差值扩展算法完成对图像像素的预处理;然后使用NTRU算法对图像像素进行加密,利用NTRU算法的加法同态性质在密文中嵌入信息,嵌入的信息得到NTRU算法加密的安全性理论保证;解密与信息提取后,利用差值扩展算法的特点可逆恢复出图像像素。采用图像的直方图及方差、信息熵、相邻像素的相关性等统计学方法,论证了在密文中嵌入信息的不可感知性。仿真实验结果表明：该算法既能实现嵌入信息后密文的正确解密,又能无损提取秘密信息,平均嵌入率可达到0.5 bpp (bit per pixel)。     

基于指纹统计特征的身份鉴别系统

指纹具有唯一性和不变性,作为个人身份标志,指纹识别技术以其安全性、可靠性、高效性,在金融证券I、T业、安防、考勤、指纹IC卡等领域正逐步得到广泛应用。概括地介绍指纹识别技术及典型的基于指纹统计特征的身份鉴别系统的结构,对指纹图像采集、图像预处理、特征提取、数据库管理及图像匹配进行分析和归纳。自动指纹识别系统的研究在过去30多年中已取得了很大的进展,但目前仍是国内外图像处理、模式识别、计算机科学等领域研究的热点。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Jane Eyre——A Feminist In The 19th Century

In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.     

《Chinese Science Bulletin》SUBJECT INDEX TO VOLUME 59(2014)

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